One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,5)(4,6)(7,8)(9,10,14,17)(11,18,20,15)(12,16,13,22)(19,24,21,23)(25,26)(27,32)(28,40)(29,34)(30,44)(31,35)(33,41)(36,50)(37,46)(38,47)(39,54)(42,48)(43,49)(45,51)(52,55)(53,56)(1,3)(2,5)(4,7)(6,8)(9,11)(10,15)(12,19)(13,21)(14,20)(16,23)(17,18)(22,24)(25,27,31,38)(26,32,35,47)(28,36,42,52)(29,37,30,39)(33,45,49,56)(34,46,44,54)(40,50,48,55)(41,51,43,53)(3,7)(5,8)(9,12,14,13)(10,16,17,22)(11,19,20,21)(15,23,18,24)(25,28,30,41,31,42,29,43)(26,33,34,40,35,49,44,48)(27,36,39,51,38,52,37,53)(32,45,46,50,47,56,54,55)(3,7)(5,8)(10,17)(11,20)(16,22)(19,21)(25,29,31,30)(26,34,35,44)(27,37,38,39)(28,41,42,43)(32,46,47,54)(33,48,49,40)(36,51,52,53)(45,55,56,50)(2,6)(5,8)(9,13,14,12)(10,16,17,22)(11,21,20,19)(15,23,18,24)(27,38)(32,47)(36,52)(37,39)(45,56)(46,54)(50,55)(51,53)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.